Establishing paleorecords in the galapagos using hydrogen isotope ratios as a proxy for climate change

Abstract

[author abstract] Global climate is heavily influenced by the hydrology of the tropical Pacific, which is characterized by a band of heavy precipitation at ~10°N in summer (~3°N in winter) known as the Intertropical Convergence Zone. Characterized by warm underlying sea surface temperatures and strong convection, the seasonal migrations of the Intertropical Convergence Zone alter the precipitation patterns of the tropical Pacific, as well as global climate. This study in Lake Escondida, Isabela Island, Galapagos, used the isotopic composition of aquatic and terrestrial biomarkers in sediments to reconstruct paleoclimates in the Galapagos. The results are consistent with previous studies, and also show evidence for a northern migration of the ITCZ after 1850 AD.